Marine cathode



March 22,1949 A. P. coLAlAco ET AL 2,465,200

MARINE CATHODE d 2m mo H m M O m ar m @m 2% 5 Filed March 20, 1947 HugqIHIZI VA VA MPH/HI! WITNESSES: 1 74w.

Patented Mar. 22, 1949 MARINE CATHODE August P. Colaiaco and Spencer M.Cork, Pittsburgh, Pa., assignors to Westinghouse Electric Corporation,East Pittsburgh, Pa., a corporation of Pennsylvania Application March20, 1947, Serial No. 736,040

2 Claims.

Our invention relates to a vapor-electric device and particularly tomeans for substantially maintaining the cathode level in avapor-electric device.

In the operation of vapor-electric devices, such as mercury-arcrectifiers, on movable platforms, such as on ocean-going vessels or onvehicles, considerable difliculty has been encountered because of thesplashing about and the formation of waves on the cathode surfaces. Alsobecause of the tilting of the containers because of the tilting of theplatform on which they are mounted or because of sudden stopping orreversal of direction, it has been found desirable to provide suchvapor-electric devices with so-called contoured cathode containers.These are cathode containers in which the upper surface of the cathodedish is contoured so that the liquid in the cathode dish will not spillover the lip at maximum inclination in the various directions, forinstance, if the container is mounted on shipboard, the roll will begreatly in excess of the pitch of the vessel so that that portion of thelip which receives the roll will be materially higher than that portionof the lip which receives the pitch. It is thus possible to provide acathode dish of restricted cross-sectional area and yet having a maximumarc-receiving opening so that the arc is substantially unrestricted inspite of the comparatively small cross-sectional area.

In these devices, it is also desirable to contour the bottom of thecathode dish so that at maximum inclination the bottom on the thenupward side is just barely covered by cathode material. However, in theoperation of vapor-electric devices, a certain quantity of material isrequired to maintain the operating condition. For example, a certainamount of the cathode material is within the arc space in the form ofoperating vapor and some of this vapor or rather the condensate thereofwill be on the sides or condensing portions of the container and in thecourse of returning from the condensing surface to the cathode dish.

In normal operation, this quantity of displaced cathode material issubstantially constant. However, when exciting devices, such asmake-alive electrodes, are used, it is desirable to maintain the cathodesurface substantially constant and when a relatively small cross-sectionof cathode dish is utilized, difficulty has been found because thequantities of cathode material necessary to maintain the operatingcharacteristic of the device frequently produces an undesirable changein the cathode level. To eliminate this difiiculty, we have providedthis relatively small cathode dish with a means for stabilizing thecathode level, preferably in the form of a reservoir, or a section ofexpanded cross-sectional area at the normal position of the cathodesurface to provide a large quantity of cathode material at the surfacelevel without greatly enhancing the total capacity of cathode material.This reservoir is preferably constructed by laterally expanding thecathode dish over a relatively short length at the point of normalcathode surface.

It is a further object of our invention to provide means for stabilizingthe cathode surface in a vapor-electric device.

It is a further object of our invention to provide a cathode structurehaving an increased quantity of cathode material at the normal cathodesurface.

Other objects and advantages of our invention will be apparent from thefollowing detailed description taken in conjunction with theaccompanying drawing, in which the figure is a fragmentary elevationpartially in section of a vaporelectric device embodying our invention.

In the exemplary embodiment of our invention, a vapor-electric device isprovided having a substantially closed container l in the bottom 2 ofwhich is secured a contoured cathode dish 3 of the type suitable formounting on movable platforms and containing a liquid cathode 4 in theform of a pool of cathode liquid, such as mercury. Cooperating with thiscathode 4 is a suitable anode 5 supported in a known manner by aninsulating device 6 attached to the top of the container I. Suitablecontrol or deionizing grids 1 may be placed between the anode 5 andcathode 4 and one or more control electrodes 8 for initiating thecathode spot may be inserted in contact with the cathode material andsuitable keepalive electrodes 9 may be utilized for maintaining thecathode spot until the establishment of a main arc between the mainanode 5 and the cathode 4. The cathode dish 3 is preferably ofrelatively small cross-sectional area and has the top H] contoured toconform to maximum variation in the various directions. Also, the bottomH of the cathode dish 3 is also contoured to provide the minimum ofcathode material. At the normal cathode level l2, a space I3 is providedfor increasing the capacity of. the cathode dish per unit lengththereof.

In the preferred embodiment, the cathode dish 3 has its diameterincreased so that the surface area at the normal surface position I 2 isincreased to several times the normal cross-sectional area of thecathode dish.

While we prefer to construct the cathode dish 3 with a unitary expandedportion l4, obviously other forms of reservoir at this particularlocation could be provided.

In the operation of the converter provided with our improved cathodedish, the evaporation of cathode material'to provide the normaloperating material for the converter will not materially reduce thecathode level as the extra cathode material at this point compensatesfor the transportation of cathode material. Consequently, the make-aliveelectrode 8 will be maintained in proper operating relation to thecathode surface for any normal operating condition.

While for purposes of illustration, we have shown and described aspecific embodiment of our invention, it will be apparent that changesand modifications can be made therein without departing from the truespirit of our invention or the scope of the appended claims.

We claim as our invention:

1. In a vapor-electric device having a plurality of main electrodes atleast one of which is a pooltype cathode, a make-alive electrodeextending into contact with said cathode, a cathode dish of small liquidcapacity for said cathode, said cathode dish being enlarged adjacent thenormal position of the cathode surface.

2. An arc discharge device comprising a substantially evacuatedcontainer, a pair of cooperating main electrodes therein, one of saidmain electrodes being a pool-type electrode, a control electrodeextending into contact with the oathode pool, a cathode dish containingthe minimum volume of cathode material and means including an annularreservoir surrounding the cathode disk at the normal position of thecathode surface, said reservoir containing a quantity of cathodematerial there being openings for the passage of cathode materialbetween the cathode disk and the reservoir to stabilize the level of thecathode material in the disk.

AUGUST P. COLAIACO. SPENCER M. CORK.

REFERENCES CITED The following references are of record in the file ofthis patent: I

UNITED STATES PATENTS Number Name Date 2,078,123 Cage Apr. 20, 19372,308,378 Marshall Jan. 12, 1943

